Marked roadway and method of making the same



United States Patent [72] Inventors Gordon M. Liddle Murray; Frank L.Christensen, Salt Lake City, Utah [21] Appl. No. 747,692 [22] Filed July25, 1968 [45] Patented Sept. 22, 1970 [73] Assignee Christensen DiamondProducts Company Salt Lake City, Utah a corporation of Utah [54] MARKEDROADWAY AND METHOD OF MAKING THE SAME 13 Claims, 4 Drawing Figs.

[52] U.S. Cl 94/1.5, 94/22, 94/33, 299/39 [51] Int. Cl E01c 23/16 [50]Field of Search 9411.5, l;2 99/39;94/31 ,33,45,22

[56] References Cited UNITED STATES PATENTS 1,698,594 1/ 1929 Hoff 94/1.5 2,112,489 3/1938 Heltzel 94/45 6/1941 Tyson 299/39X 2,673,725 3/1954Coates 299/39 2,855,189 10/1958 Lewis 299/39 3,232,187 2/1966 Brigham94/1.5 3,396,639 8/1968 Lemelson 94/ 1.5 FOREIGN PATENTS 564,507 2/1958Belgium 94/1.5

OTHER REFERENCES Proceedings of Highway Research Board, June 24, 1938, Ps 3 Primary Examiner-Jacob L. Nackenoff Attorney-Bernard Kriegel side ofthe roadway for facilitating drainage during inclement weather.

Patented Sept. 22, 1970 3,529,517.

Sheet 1 of2 i m 4 A Ciro/200M M. Ii /001.5

E li emvxl Cq/e/s rs/vss/v Iv vEA/ToeS.

Patented Sept. 22, 1970 I/vvE/vro/es.

aM/ W The stripes or other markings on highways and other roads, whichare employed to designate the center of the roadway or lanes for thepassage of traffic thereon, pose problems respecting visibility of themarkings or stripes. on the one hand, and durability of such markings orstripes, on the other hand.

In inclement weather. and particularly during the twilight or nighthours, the usual roadway markings and stripes which designate the lanesof traffic, as well as the middle of the roadway or the sides thereof,are frequently not clearly visible. This is particularly true when thestripes or markings are beneath a layer of water during and followingrainfall. In order to avoid the lack of visibility of the usual stripesand markings formed by the application of reflective coatings to theroadway surface, elevated reflectors may be employed, but suchreflectors are not practical in certain geographical areas whereaccumulated snow on the roadway requires the use of road scrapingequipment in order to open the roadway to the passage of vehiculartrafiic.

Moreover, the provision of a suitable reflective coating for use in thestriping or marking of roadways, which coating will stand heavyvehicular traffic, has long been a problem, inasmuch as the usual paintor other reflective coating material rapidly wears away, therebyrequiring substantial expenditures in the maintenance of the roadwaymarkings and stripes.

With the foregoing problem in view, the present invention provides aroadway having stripes or other markings thereon and a method of formingstripes or other markings in roadway surfaces, which stripes or-markingsare more readily visible during the period that the ordinary stripes ormarkings on highway surfaces are not clearly visible due to poorlighting, particularly when water is on top of the reflective stripes ormarkings during inclement weather.

The present invention also provides a roadway having stripes or markingsthereon and a method of forming such stripes or markings, which are moredurable than the conventional surface stripes or markings heretoforeemployed on roadways.

More particularly, the present invention contemplates the formation ofparallel ridges and intervening spaces extending along the roadway inthe traffic supporting surface, at least the side walls of the ridgesdefining the intervening grooves or valleys having reflective paint orcoating material applied thereto, and the crest of the ridges also beingcoated in a specific sense, so that the reflective coating is clearlyvisible to a motorist, but the major extent of the coated area isrecessed beneath the traflic bearing surface of the highway or roadwayso as to be protected from the usual wear caused by heavy vehiculartrafiic.

The roadway and the method of the present invention also contemplate theformation of drain channels or grooves extended transversely of theridges and intersecting the grooves defined between the ridges so as toeffectively drain off water from the striped or marked regions of theroadway to the low side of the roadway, thereby enhancing visibility ofthe roadway markings or stripes during inclement weather.

Inasmuch as the stripes or markings in the roadway made in accordancewith the present invention are substantially recessed, or at the peaksof the ridges do not project above the nonnal traffic supporting roadwaysurface, the roadway may be readily scraped by the usual road scrapingequipment required to clear highways of snow and ice, in certaingeographical areas where deposits of snow and ice on the roadway poseproblems.

More specifically, the invention contemplates forming in a roadwaysurface a series of parallel grooves and ridges by milling the grooves,employing a milling cutter which may be of the type involving arotatable milling cutter having diamonds embedded about the periphery ofthe milling cutter on ridges and in valleys of the milling cutter,which, upon revolution of the milling cutter and travel of the cutteralong the roadway, will form mating valleys and ridges in the roadwaysurface, the side walls of the ridges of the milling cutter defining thegrooves therebetween being disposed at an angle so as to provide in theroadway ridges having convergent side walls forming the valleystherebetween, so as to present laterally projecting surfaces to whichthe reflective coating material may be applied, and whereby a clearlyvisible road marking will be provided.

This invention possesses many other advantages and has other purposeswhich may be made more clearly apparent from a consideration of a formand method embodying the invention. This form and method are shown anddescribed in the present specification and in the drawings accompanyingand constituting a part thereof. They will now be described in detail,for the purpose of illustrating the general principles of the invention;but it is to be understood that such detailed description is not to betaken in a limiting sense, since the scope of the invention is bestdefined by the appended claims.

Referring to the drawings:

FIG. 1 is a view showing in perspective a section of roadway havingmarkings applied thereto in accordance with the invention;

I FIG. 2 is a fragmentary view in vertical section, and on an enlargedscale, as taken on the line 22 of FIG. l;

' are the valleys 3, so as to effectively provide a stripe which, in-

FIG. 3 is a fragmentary view in vertical section, and on an enlargedscale, as taken on the line 3-3 of FIG. 1; and

FIG. 4 is a view corresponding to FIG. 2, but illustrating a modifiedroadway construction.

As seen in FIG. I, the invention involves the production of a roadway,generally denoted at R, and including a suitable road bed B and surfacematerial S composed of concrete, or the like. The surface material Sprovides a traffic bearing surface T, which, in accordance with standardpractices, should be formed on a suitable grade, as indicated by theangle A, so as to enable lateral drain-off of water from the trafficsupporting surface T of the roadway during inclement weather. Extendedalong the roadway are markings in the form of stripes I, which typicallywould define the center of a roadway and/or desired traffic lanes alongthe roadway between which the vehicles are to travel. Such stripes l aregenerally in accordance with prior practices provided by the simpleapplication of a stripe of reflective coating material or paint to thetraffic supporting surface T at desired locations.

However, traffic changing of lanes must cross over the stripes 1, and inareas of heavy traffic, the stripes are, therefore subjected to severewear. On the other hand, where such stripes designate stop lines orcross traflic lines, each and every vehicle passing over the roadwaysurface T must also pass over the marking stripes so that the wearproblem is, perhaps, accentuated.

In the event that the road surface T is grooved by the use of millingcutters of the conventional diamond or saw types to smooth out surfaceirregularities and enhance traction, the 55' ridges and grooves arenarrow or closely spaced so that paint stripes applied to such surfacesare not significantly protected or more visible in inclement weather.

However, in accordance with the present invention, the stripes 1comprise a series of laterally spaced, parallel ridges 2 and interveningvalleys 3. As best seen in FIG. 2, the ridges have crests 2a whichproject substantially to the plane of the traffic supporting surface T,whereby to afford support for vehicle tires passing over the stripes, sothat the tendency to cause erratic vehicle travel will be eliminated.Moreover, in the embodiment of FIG. 2, the ridges 2 are arcuate in fonn,as

cross-section, is sinuous. This sinuous form of the adjacent ridges andvalleys provides side walls 2b on the ridges, which, essentially, aredivergent relative to one another, but convergent with the adjacentsidewall of the adjacent ridge so as to provide substantial lateralsurface projection for the application of a coating of reflective paintor other material, as generally denoted at 4. I i I As vehicular trafficpasses over the stripes defined by the ridges 2 and valleys 3, thecoating at the crest 2a of the ridges is subjected to the maximum wear.but the side walls or flanks 2b of the ridges 2, being recessed belowthe normal traffic supporting surface T, are protected from such wearand, therefore, will endure for substantially greater period of timethan would the usual stripe or marking applied directly to the surfaceT.

In order to prevent the stripes 1 from being obscured during periods ofpoor visibility, for example. during the twilight hours in inclementweather, when water may be upon the surface of the roadway. lateraldrain channels are provided at appropriate spaced locationslongitudinally of the stripes 1, these lateral drain channels 5 having abase 6 which is preferably as deep as the valleys 3, so that the drainchannels 5 extend laterally through each of the ridges 2 and intersecteach of the valleys 3, In addition, the drain channels 5, as seen inFIG. 3, extend laterally past the marginal valleys and, moreparticularly, the drain channels include an outlet portion 5a whichmerges with the traffic supporting surface T of the roadway downgradefrom the lowest of the valleys 3. The base 6 of the drain channels 5also is at an incline relative to the horizontal plane as represented bythe angle C as seen in FIG. 3, whereby water from the valleys3 mayquickly drain off laterally through the drain channels 5 in thedirection of the nonnal roadway grade.

Referring now to FIG. 4, a modified roadway construction is shown inwhich the ridges 2 are of greater lateral extent than in the previouslydescribed embodiment. and include a flat crest surface 2a extendedlaterally substantially in the plane of the traffic supporting surface Tof the roadway. In this embodiment, the valleys 3 are defined byopposing angular side walls 2b, as in the previously describedembodiment; and, as in the previously described embodiment, the roadwayis provided with lateral drain channels 5 so as to drain the surfacewater from the valleys 3, such drain channels traversing the ridges toestablish communication with the valleys 3. Likewise, a reflective paintor other coating 4 is applied to the ridges and in the valleys. In thisembodiment, the flat crests 2a have greater lateral extent in the planeof the road surface T than the crests of the first described embodiment,so as to afford better engagement with vehicle tires and reducedtendency to cause erratic wheel movements.

In the practice of the present method of forming highway markings orstripes, the lateral drain channels 5 may be milled or formed in thesurface T either prior to or subsequent to the milling or forming of theridges 2 and grooves or valleys 3. Also, these drain channels 5 may beformed either prior to or following the application of reflective paintor other coating material to the ridges and grooves by any of theconventional methods.

While one specific form of lateral drain channel 5 has been illustrated,it is apparent that other specific forms of drain channels may beemployed. For example, the drain channels may be formed with the samemilling cutter employed to form the stripes I, and in such a case, thevalleys or grooves 3 cumulatively would provide substantial lateraldrain flow area. Other forms of drain channels, as well as otherspecific shapes of valleys 3 and ridges 2, will be apparent.

We claim:

1 1. In a concrete roadway having a normal vehicle supporting surfaceand a traffic lane extending along said surface, said concrete roadwayhaving a lane marking defining a side boundary of said lane, saidmarking comprising valleys formed in the concrete and extendingdownwardly of said surface and longitudinally of said lane and parallelto the center line of said lane, said valleys being separated byintervening laterally spaced concrete ridges integral with the concreteroadway and extending longitudinally of said lane and parallel to thecenter line of said lane, said ridges commencing at said normal vehiclesupporting surface and extending downwardly thereof to define saidvalleys therebetween. the opposing side walls of ridges forming eachintervening valley converging downwardly toward each other to the bottomof each valley,

and a reflective coatin on at least the side walls of said ridges. 2. Aroadway as de med in claim I, wherein said ridges and valleys are oftransversely sinuous form.

3. A roadway as defined in claim 1, wherein said ridges have flat uppersurfaces.

4. A roadway as defined in claim I, wherein a drain channel extendslaterally through said ridges and intersects said valleys.

5. A roadway as defined in claim 1, wherein said coating is also on thecrests of said ridges.

6. A roadway as defined in claim 1, wherein said coating is also on thecrests of said ridges and in the bottoms of said valleys.

7. A roadway as defined in claim 1, said roadway having a drain channelextending laterally across said valleys and ridges and having a bottomat least as deep as the bottoms of said valleys.

8. A roadway as defined in claim 1, said roadway having a drain channelextending laterally across said valleys and ridges and having a bottomat least as deep as the bottoms of said valleys, the bottom of saiddrain channel feathering out to said normal vehicle supporting surfacein laterally spaced relation to said ridges and valleys.

9. The method of providing a lane side boundary marking in a hardconcrete roadway having a normal vehicle supporting surface and atraffic lane extending along said surface, comprising cutting spaced,longitudinally extending parallel valleys in said hard concrete roadwayextending downwardly from said normal surface and parallel to the centerline of said lane to provide intervening parallel ridges extendinglongitudinally of said lane and parallel to the center line of saidlane, said valleys being cut to provide side walls of said ridgesforming each intervening valley that converge downwardly toward eachother to the bottom of each valley, and then applying a reflectivecoating on at least the converging side walls of said ridges.

10. In a method as defined in claim 9; said valleys being cut to providesaid intervening ridges which commence at said normal vehicle surfaceand extend downwardly therefrom.

II. In a method as defined in claim 9; cutting a drain channel in saidhard concrete roadway extending laterally across said ridges and valleyswith the bottom of said channel at least as deep as the bottoms of saidvalleys.

12. In a method as defined in claim 9; also applying said reflectivecoating to the crest of said ridges.

13. In a method as defined in claim 9; said valleys and interveningridges being cut by forcing rotating cutter means against the roadwaywhile moving said cutter means longitudinally along said roadway.

